I removed the boiler from the frame for shipping reasons, weight reduction to be precise.

It's a compact 2 group machine.

Prior to this it sounded like there was an air block in the pipes mainly after the group heads had been run. It groaned like the plumbing in an old house.

Now that it is all back together is there a trick to refilling the boiler and running water through all the pipes to avoid air blocks and if there are air blocks what is the best way to get rid if them?